Blast furnace tuyere



Patented ug. 6, 1946 BLAST FURNACE 'rUYaE John H. Sprow, Jackson, Ohio IApplication August 22, 1945, Serial No. 612,015l

Claims.

My invention relates to blast furnace tuyres.

It has to do, more particularly, with va tuyre for inserting acombination concentrated stream of air, as well as a stream of air whichhas a spreading effect, into a blast furnace.

In the past, many attemptsY have been made to provide a blast furnacewith a tuyre `having a blast of air which will penetrate to thecenter ofthe furnace and, at the same time, will permit the spreading of airaround the sides of the furnace in order to aid in the reduction of theore and fuel at that point as well as at the center. In other words, atuyre which furnishes a penetrating blast of air that does not have a,spreading iiow. To overcome this difficulty, it has been necessary tomake and position tuyres of two sizes in the furnace in order toaccomplish this uniform reduction of materials placed in the blastfurnace. The main diiculty in using two sizes of tuyres is that it cutsdown the overall blast into the furnace and thus reduces the eiiiciencyof the furnace. Various devices have been inserted in tuyres for varyingcross-sectional size, but they have quite generally resulted in theformation of back pressure and ineicient blasting. At the present time,narrow tuyres are placed along vside of wide-nosed tuyres in thel boshof the blast furnace. The narrow tuyres give the penetrating blast whilethe wide-nosed tuyres give a fan-like spreading action for aiding in thereduction o-f the materal at thesides of the furnace. Even with thegreat number of tuyres now positioned in the furnace, there is still anuneven distribution, and where the narrow tuyres appear inthe furnace,pilasters or slag deposits form around the sides of the furnace adjacentthe narrow-nosed tuyre. This formation of the pilasters greatly'reducesthe life of the individual tuyre, therefore, necessitating replacementssooner than ordinarily expected. Furthermore, as indicated above, the

" surface.

One of the objects of my invention is to provide a tuyre which iscapable of furnishing both a penetrating and spreading blast in afurnace.

Another object of my invention is to provide a which will permitfurnishing of a certain quantity of air but in varied velocities to thematerial in the furnace.

Another object of my invention is to provide a tuyre which has twodimensions'in crosssectional diameter which provides for a penetratingblast and a spreading blast wlnle at the same time maintaining the sametotal quantity of air inserted in the furnace.

Another object of my invention is to provide a tuyre having its innerside wall surface divided into four sectional units, two of said unitsbeing spaced closer together than 4the other two units yet forming noobstruction to the blast of air inserted from the blast main.

Another object of my invention is to provide a tuyre which will moreeiiiciently reduce thematerial in the furnace by a uniform distributionof air blast to the center of `the furnace as well as around the sidesthereof.

Another object of my invention is to provide a tuyre which will have apenetrating blast action and at the same time substantially reduce theformation of ypilasters around the sides of the bosh portion of thefurnace.v

Another object of my invention is to provide a tuyere having at leasttwo diameters in cross section which will facilitate a reduction of theore uniformly throughout the furnace.

Various other objects and4 advantages will be apparent from thefollowing detailed description and the drawing where-in similarcharacters of reference designate corresponding parts and wherein Figure1 is a front end View of the tuyre, constructed according to myinvention, taken along line l-l of Figure 2.

Figure 2 is a vertical sectional view of the tuyre taken along line 2-2of Figure l.

Figure 3 is a rear end View of the tuyre taken along line 3-3 of Figure2 and showing the plugged opening for water cooling the tuyre.

Figure l is a fragmentary perspective View of the tuyre, partly insection, illustrating the marked taper of one of the sections of theinside Figure 5 is a side elevational View of the lower end of the blastfurnace showing the location of the tuyres with reference/to `the boshand hearth. A

Figure 6 is a top plan View of the tuyres in Iplace in theblast furnacetaken along line SQ-6 of Figure 5'and showing thetwoff'old distributionof the air blast.

.tuyre of varying cross sectionl'at thelnose end u55 Referring to theVdrawing, more particularly to Figure 2, I illustrate a hollow tuyre I offrustroconical shape. The tuyre I is tapered toward the nose end 2.

The tuyre I is provided with a conventional water jacket 3 for keepingthe inner wall surfaces cool and said water jacket is supplied with asteady stream of water through a plurality of orifices 4 shown at therear end thereof of the tuyre in Figure 3. A

-The inner wall surface of the tuyre is so formed as to provide fourlongitudinally extends ing wall segments each of which varies in widththroughout; its length. These segmentsjconstitute the diametricallyopposed pair of Walls 5 and the diametrically opposed pair of walls 6which pairs are located at rightH-anglestdeach other. Along thelongitudinal edges of the walls there are provided the shoulders 6a thattaper rearwardly from the nose 2 to a point where they 'converge withthe walls 5, as atha.A Thus, as shown in Figure l, the walls 6 :convergetowards each other at the nose resulting in a reduction of the diameterof the nose at this area. Consequently, there results a tuyre which hasanarrow nose portion and 'a wide nose portion atright angles toeachother. The diameter of the rear end'of 'the tuyre, however, isuniform. This wall arrangement in a single tuyre produces'a 'combinationtuyre blast which will have -both a -penetrating and a spreading actionwhich must usually be accomplished by having vboth'a wide-nose and anarrow-nose tuyre.

In other words, the tuyre lI illustrate in the figures of the drawingwill permit a blast of air into the furnace of the type shown vin Figure6 which has 'a concentratedstream to the center and also a spreadingstream which allovvsa uniform distribution 4of the charge of vairoverVthe entire interior area of the furnace. seen `from Figure 2, thetapered wall segment 6 varies in kcross-sectional diametersofV the tuyreand the air passing through vthe tuyre will be concentrated by thenarrower "diameter along the horizontal axis dueto 'thenarrownosed por--tioned formed by the tapered`wall segment and the air passing alongtheregulartapered walliportion 5 will Aproduce va spreading action. I thusprovide a tuyre which is in'eifeotequivalent of two tuyres of varyingsizes.

YI have found that vtapering the two 'equal Vsegments of the wallportion of a tuye'rein this manner does not form back pressures upon theblast main 3 shown in Figure 5. Pipes 1 "are 4 duce the proper blast ofair required within the furnace.

For example, if the particular furnace requirements call for a morepenetrating blast, the tapered segment 6 can be made 4-inches indiameter, and the wider portion 5, 6-inches in diameter. It will be seenthat this area will be of the same ratio as that of a 5-inch tuyre andstill retain the velocities and penetration characteristics of thetuyre.

While I show in Figure 1 the vertical diameter the widest, it isunderstood that the tapered diameter 6 can be positioned along thevertical axis and have the Widest diameter portion of the tuy're'nose'along the horizontal axis. This type of. tuyre may be rotated todifferent positions at intervals so 4that pilasters which form adjacentthe narrow-nosed portion 6 of the tuyre can be burnt off by positioningthe wide-nosed portion 5 of the tuyre and turning the narrow-nosedportion tthe .position where the widsd 'p'rtion had been. Furthermore,Ywhile I 'show the tuyre nose as being divided 'into quarter sgme'nts,it is understood that I also wish 'to use a tuyre wherein a plurality ofvarying diameters aregpresent at the'nose'end and not necessarilylimited to two, as shown'in the cl'ravvin'g.` Itis understood that thetuyre can be dividedinto a vnumber of other segments which may havecharacteristics similar tothe present type of tuyre shown intheaco'mpanyig drawing. 'At is important. that the degree of Ataper Yof thesmaller diameter Vsegment atthe 'nose endbefvei'y slight along -the Wallof 4the tuyre so that `it AS will bev connected to the rear ends of thetuyeres 1 vand to Figure '6 illustrates the spread of air as well as theconcentrated blast which reaches tothe-center i of the furnace. Thetapered wall segments E fof the tuyre furnish the means for 'theconcentrated blast while 'the 'wall segments 5 furnish the spreadingblast.

With this arrangement, I am able to vary fthe blast in velocity andstill maintainth'e same'crosssectional area of tlietuyre by making thediameteriof the 'wallrportions indicatediby'the segments 5, one-halfinch larger than `theusual rtuyre 'size 4and by reducing the' diameter`of the f wall 6, one-half inch. This enables me to procomesuto a finepoint at the back end of the tuyre. If the taperNi's too marked, backApressureswill be created in the tuyre which are definitelyundesiderable. It is myrintention, therefore, that the tapered segmentscoincide with the Acircular 'surface ofthe sider Wall 5 at the .point"5a, at the rear end of the tuyre. Atth'e nose endof the tuyereLIdisclose a thickened portion shown best invFigure l by Athe numeral 6.

A nI/ t will AIce apparent from lthe-above description thai-, 1 haveprovided a tuyre having many advantages over present-day tuyres in usein blast furnaces. AThis tuyre has the equivalent-flow o fV air as -botha Ywide or narrow-nosed tuyre and alsoretains the proper amount ofairblast required for the type furnace in use. The variation of thecross-sectionalearea ofmywtuyereperfmits both a penetrating andaspreadingblast of air'into a furnace thus aiding the reduction of the ore in a more efficient manner. Itwillbe seen that this tuyre is sodesigned -thatfitis particularly adaptable to preventthe Vformation ofrpilasters around the nose ofthe tuyre andfalsof-mai-nf tain aconcentrated blast vof --airdnto the center of the furnace.Anotheradvantageof my tuyre is that it is simple in construction y-anddoes-not form back pressure as do -other tuyres having Vrestricted noseend openings., Many other 4advantages will be-apparent from theabovedescription, the drawing and the following claims.

y Having thus 'described my invention, what I claim is:

l. iA -blast furnace tuyre of -frustroeconical shape having a circular''rear end` portion "andqa nose end portion having -oppositely spacedr`circular arcs formed by taperingY parts rofthe wall intermediate thevrear e'n'dfandA the'fnose en'dithus formingthe saidcoricentriciarcsfvaryiiig widths so fas `to4 vary' the 'velocity 'and ldirection "of theFair inserted "in the rear end 'of 'the ltuyre' 'to be forced into theblast furnace.

2. A tuyre of the type described comprising a tapered wall portion, asecond wall portion tapered to a greater degree than Saidfirst-mentioned wall portion, saidrwall portions forming segments of acircle which vary the diameter of the nose end of the tuyre, saidsegments having similar segments oppositely disposed and tapered in thesame degrees, respectively, as said first two-mentioned segments so thatthe diameter of the tuyre at the nose end presents two diameters forinserting air in varying velocities and directions.

3. A tuyre of the type described comprising a tapered wall portion, anadditional wall portion tapered to a greaterdegree than saidfirst-mentioned wall portion, said wall portions forming segments of acircle which vary the diameter of the nose end of the tuyre, saidsegments having similar segments oppositely disposed and tapered in thesame degree, respectively, as said rstmentioned segments so that thenose end of the tuyre presents two diameters for inserting air invarying velocities and directions.

4. A tuyre of the type described having a circular rear end portion anda nose portion including concentric arc segments of varying diameters,the inner wall of said tuyre including wall segments arranged in pairsof oppositely disposed walls, the walls of some of said pairs convergingtowards each other and towards the tuyre axis to agreater extent thanother of said pairs.

5. A tuyre of the type described having a nose portion includingsections which are relatively angularly disposed and are of varyingwidths so as to direct the tuyre blast differently, the inner wall ofsaid tuyre including wall sections arranged in pairs of oppositelydisposed Walls, the walls of some of said pairs converging towards eachother and towards the longitudinal center line of the tuyre to a greaterextent than other of said pairs.

JOHN H. SPROW.

